DESCRIPTION TenCate s BT250E-1 resin system is a 121 C (250 F) cure epoxy prepreg system with excellent toughness and strength. It provides an outstanding surface finish under vacuum bag/oven cure only. The resin system, which is self-adhesive to honeycomb and foam core, is MIL-R-9300 qualified and makes a great choice for many applications in the low to medium service temperature range. FEATURES > > Excellent system for out of autoclave cure > > Toughened for good impact resistance > > MIL-R-9300 qualified > > Ideal for low to medium service temperature applications PRODUCT TYPE 121 C (250 F) Cure, Epoxy Prepreg System TYPICAL APPLICATIONS > > Secondary aircraft structures > > Radomes with glass, quartz, and Kevlar > > Reflectors > > Sporting goods > > Knee braces and other related medical items > > General purpose composites SHELF LIFE Tack Life: Out Life: Frozen Storage Life: Up to 30 days at ambient Up to 30 days at ambient 12 months at -18 C (<0 F) Tack life is the time during which the prepreg retains enough tack, drape, and handling for component lay-up. Out life is the maximum time allowed at ambient temperature before cure. *Ambient is 18 22 C (65 72 F) *Out life tested by SBS on 8-ply 15 x 15 cm (6 x 6 ) fabric laminate, cured in an out-of-autoclave/vacuum bag only (OOA/VBO) environment with 914 948 mbar (27 28 in Hg). Users may need to separately evaluate out life limits on thicker, larger, and more complex parts. TYPICAL NEAT RESIN PROPERTIES Density T g Dielectric Constant Loss Tangent Moisture Absorption Tensile Strength Tensile Modulus 1.17 g/cc Tensile Strain 2.5% Compression Strength Compression Modulus Flexural Strength Flexural Modulus Flexural Strain 5.5% CTE Dielectric Constant at 10 Ghz on 4581 quartz Loss Tangent at 10 Ghz on 4581 quartz 125 C (257 F) 3.0 at 10 GHz 0.019 at 10 GHz 2.0% after 24 hr water boil 75 MPa (10.9 ksi) 3 GPa (0.44 Msi) 115 MPa (16.7 ksi) 2.8 GPa (0.4 Msi) 156 MPa (22.6 ksi) 3.4 GPa (0.50 Msi) 71 ppm/ C (39 ppm/ F) 3.26 0.0081 More information: info@tcac-usa.com (North America/Asia/Pacific) tcacsales@tencate.com (Europe/Middle East/Africa) Page 1/5
ELECTRICAL PROPERTIES OF COMPOSITE LAMINATES BT250E-1 (7781 Fg) C/X Band 8 18 GHz Ku/K Band 18 26.5 GHz Ka Band 26.5 40 GHz Q & U Band 40 60 GHz Dielectric Constant 4.52 4.48 4.45 4.42 Loss Tangent 0.019 0.018 0.017 0.016 MECHANICAL PROPERTIES Properties Condition Methods Results Tensile Strength 0 RTD ASTM D 3039 502 MPa 73 ksi Tensile Modulus 0 RTD ASTM D 3039 24.5 GPa 3.6 Msi Compressive Strength 0 RTD ASTM D 3410 485 MPa 70 ksi Compressive Modulus 0 RTD ASTM D 3410 24.8 GPa 3.6 Msi Flexural Strength 0 RTD ASTM D 7264 602 MPa 87 ksi Flexural Modulus 0 RTD ASTM D 7264 21.6 GPa 3.1 Msi Short Beam Shear Strength RTD ASTM D 2344 62.3 MPa 9.0 ksi Laminate data - 7781 Fg reinforcement, 300gsm FAW. * All properties normalized to 60% fiber volume except ILSS. (Fiber volume 40 50%) MECHANICAL PROPERTIES Properties Condition Methods Results A Results B Tensile Strength 0 RTD ASTM D 3039 767 MPa 112 ksi 797 MPa 116 ksi Tensile Modulus 0 RTD ASTM D 3039 57.3 GPa 8.3 Msi 59.0 GPa 8.6 Msi Compressive Strength 0 RTD ASTM D 3410 518 MPa 75 ksi 570 MPa 83 ksi Compressive Modulus 0 RTD ASTM D 3410 55.2 GPa 8.0 Msi 57.7 GPa 8.4 Msi Flexural Strength 0 RTD ASTM D 7264 752 MPa 109 ksi 790 MPa 115 ksi Flexural Modulus 0 RTD ASTM D 7264 51.2 GPa 7.4 Msi 53.6 GPa 7.8 Msi Short Beam Shear Strength RTD ASTM D 2344 61.9 MPa 9.0 ksi 63.5 MPa 9.2 ksi (A) Laminate data - 3K PW graphite, 250gsm FAW. (B) Laminate data - 3K 8HS graphite laminate, 368gsm FAW. *All properties normalized to 60% fiber volume except ILSS. (Fiber volume 40 50%) Page 2/5
BT250E-1 Epoxy Prepreg: Cure cycle Heat up at 1 3 C (2 5 F)/min Hold at 125 C (250 F) for 60 minutes minimum. *Part must be dwell at this temp. Oven temp. may not reflect actual part temperature. Below 71 C (160 F), release pressure and remove. (Temperature based on lagging thermocouple) Apply 25 inches Hg vacuum minimum. Apply 1 3.4 bar, 30 100 psi pressure to autoclave (optional). BT250E-1, Lot# 041801-3.3M2, 1.6 C (3 F)/min, 25 C 121 C (77 F 250 F), hold 60 min Page 3/5
EPOXY PREPREG, ADHESIVE, AND RESIN GUIDELINES AND HANDLING PROCEDURES The following guidelines are provided to our customers to assure that best practices are used to attain the best results from TenCate Advanced Composites (TCAC) epoxy products. Keep in mind that these procedures represent best practices for all composite prepreg and adhesive materials. FREEZER STORAGE Epoxy resin materials have good shelf life at room temperature, however, the life and performance of the material is best preserved with the following basic guidelines. Refer to the shelf life included in the product certifications. The epoxy material should be sealed in an airtight bag and kept frozen below -18 C (0 F) when not being used for longest life and most consistent performance. A good safety measure is to have a bag of desiccant (silica moisture absorber) in the core of the prepreg roll to assure the best protection from moisture imgression. MOISTURE ABSORPTION AND SENSITIVITY While very resistant to moisture absorption after cure, epoxies can be adversely affected by moisture uptake prior to cure. For this reason, all materials must be completely thawed to room temperature prior to opening the sealed bag to avoid condensation on the material. Also, it is good practice to keep prepreg and in-process hardware in a sealed bag or vacuum bag if it will be exposed to the atmosphere for long periods of time. HANDLING OF MATERIALS When handling any prepreg materials, one should always wear clean, powder-free latex gloves. This will assure that no hand oils are transferred to the prepreg and/or composite during processing. The presence of oils in the part could lead to problems in both mechanical and electrical performance of the part. This also guards against dermatitis that may occur with some users. NONMETALLIC HONEYCOMB AND FOAM CORE USE When using nonmetallic honeycomb and foam core materials for sandwich structures, the materials should always be dried in an oven prior to lay-up to drive off any moisture that may be in the core. The core should be cooled in the presence of a desiccant to avoid moisture uptake. Following drying, it is always best to use the material as soon as possible. Recommended core dry time/temp: 121 C (250 F) for 3 4 hours. DEBULK LAY-UP MATERIAL SEQUENCE FROM TOOL SURFACE TO BAGGING MATERIALS 1. Bottom Tool 2. Non-porous FEP 3. Prepreg 4. Porous TX1040 5. Non-porous FEP 6. Caul plate 7. Breather (woven or thick breather) 8. Vacuum bag 9. Repeat above procedure A robust debulking procedure is necessary to minimize entrapped air between plies as shown in Figure 1. Vacuum level should be at least at 27 in. Hg. BT250E-1 was debulked at ambient every 4 plies for 5-10 minutes. An additional ply of porous Teflon coated glass (TX1040) was used to help with the removal of entrapped air, and it was replaced every 2-3 cycles. Page 4/5
TYPICAL COMPOSITE LAMINATE STACKING SEQUENCE List of Materials 1. Tool aluminum, steel, Invar, composite (tool plates must be release coated or film covered) 2. Release coat or film Frekote 700NC or 770NC, FEP, TEDLAR 3. Silicone edge dams thicker than laminate 4. Laminate 5. Release film 6. Caul plate aluminum, steel, Invar, silicone rubber sheet (metal caul plates must be release coated or wrapped) 7. 2.2 oz/yd 2 polyester breather 1 or more 8. Vacuum bag 9. Vacuum sealant 10. Glass yarn string (alternatively or additionally breather may wrap over top of dam to contact edge) Figure 1 Revised 05/2018 Page 5/5 2018. All data given is based on representative samples of the materials in question. Since the method and circumstances under which these materials are processed and tested are key to their performance, and TenCate has no assurance of how its customers will use the material, the corporation cannot guarantee these properties. TenCate, (TenCate) AmberTool, (TenCate) Cetex, TenCate MicroPly, and all other related characters, logos, and trade names are claims and/or registered trademarks of Koninklijke Ten Cate B.V. and/ or its subsidiaries in one or more countries. Use of trademarks, trade names, and other IP rights of Royal TenCate without the express written approval of TenCate is strictly prohibited. 18410 Butterfield Blvd. Morgan Hill, CA 95037 USA t +1 408 776 0700 2450 Cordelia Road Fairfield, CA 94534 USA t +1 707 359 3400 Amber Drive, Langley Mill Nottingham, NG16 4BE UK t +44 (0)1773 530899 www.tencatecomposites.com info@tcac-usa.com (North America/Asia) tcacsales@tencate.com (Europe)